A single-blinded study, also known as a single-masked study, is a type of research study in which either the participants or the investigators are unaware of certain key information related to the study.

In a single-blinded study, the participants are typically aware of their assigned intervention or treatment, but the investigators who interact with the participants and collect the data are not informed. This helps to minimize potential biases or influences that could affect the study outcomes. The purpose of blinding in a single-blinded study is to reduce the risk of subjective bias by keeping the participants and investigators "blinded" to certain aspects of the study.

By blinding the investigators, it helps to prevent conscious or unconscious influences on the assessment or reporting of study outcomes. This can be particularly important when subjective measurements or assessments are involved, such as pain ratings, quality of life assessments, or subjective observations.

However, it's important to note that in a single-blinded study, the participants are not blinded to their treatment assignment. They may still be aware of the intervention they are receiving, which could potentially introduce some bias.

In contrast, a double-blinded study involves blinding both the participants and the investigators, meaning that neither group knows the treatment assignments. Double-blinding is often considered the gold standard in clinical research as it helps to minimize both participant and investigator biases.

Blinding, whether single or double, is a common practice in clinical trials and other research studies to enhance the rigor and validity of the study results. It helps to ensure that the outcomes are attributed to the interventions being studied rather than the expectations or biases of the participants or investigators.